RHOS 4.0 python-nova should require python-cinderclient>=1.0.6 to support volume migration. (Not packaged in RHOS yet.)
We've not yet started track client dependencies to this level of detail as we'd be constantly bumping the version numbers of the matrix of interdependencies. I've moved this to the cinderclient component for now, to ensure it's updated.
Auto adding >= MODIFIED bugs to beta
This is a bug in openstack-nova at this point - flipping components. Please re-ack as appropriate.
Current openstack-nova has: Requires: python-cinderclient not: Requires: python-cinderclient >= 1.0.6
python-cinderclient 1.0.7 is currently available. We provide distribution as a whole so we prefer to provide right packages over requiring explicit versions and bumping these around as Pádraig explained.